Bulldozer blade with vibrating ripper shank

ABSTRACT

There is disclosed a bulldozer modified with an extendable and retractable ripper on one or both vertical edges of the bulldozer blade with means to move the ripper with a reciprocal or vibrating motion to provide an up-and-down breaking motion when the tip of the ripper is underground.

United States Patent [191 Adams et al.

[ Dec. 31, 1974 BULLDOZER BLADE WITH VIBRATING RIIPPER SHANK Inventors: Ronald E. Adams, Dubuque, Iowa;

Eugene M. Wilson, Joliet, Ill.

Assignee: Caterpillar Tractor Co., Peoria, Ill.

Filed: Jan. 11, 1974 Appl. No.: 432,495

[1.5. CI. 172/777, 172/802 Int. Cl E02f 3/12 Field of Search 172/802, 40, 777, 778,

References Cited UNITED STATES PATENTS 12/1957 Mullin 172/777 2,993,285 7/l96l Hoxie 172/777 3,039,209 6/1962 Cron et al 37/98 X 3,238,646 3/1966 Oldenburg l72/40 X 3,559,749 2/1971 Fryrear l72/802 Primary Examiner-Stephen C. Pellegrino Attorney, Agent, or Firm-Phillips, Moore,

Weissenberger, Lempio & Strabala [5 ABSTRACT There is disclosed a bulldozer modified with an extendable and retractable ripper on one or both vertical edges of the bulldozer blade with means to move the ripper with a reciprocal or vibrating motion to provide an up-and-down breaking motion when the tip of the ripper is underground.

7 Claims, 4 Drawing Figures Patented Dec. 31, 1974 I 2 Sheets-Shae t 1.

Patented Dec. 31, 1974 3,857,447

2 Shoots-Sheet 2 BACKGROUND OF THE INVENTION DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS FIG. 1, a bulldozer blade is attached with conven- It is difficult for bulldozers to work hard-crusted or 5 i nal nkage 11 to a a t (n shown) to m a rocky ground. The bulldozer blade has difficulty penetrating such ground and it gets hung up on rocks. In the past, plowing of such ground has been handled by the operator penetrating with the blade as far as possible after which the blade is raised slightly to break the difficult ground upwardly, after which the blade is lowered and a further penetration is made. This manner of dealing with such ground is very time consuming and, accordingly, expensive.

Rippers attached to the lower edge of a bulldozer blade have been used. Rippers are thin pronged-like extensions that extend beneath the lower edge of the blade to tear up the ground before the blade is used. Rippers relieve the difficult problem, but even rippers have difficulty in prying rocks and stumps loose; and when a bulldozer can no longer move a ripper forward, it must stop, raise the ripper slightly to break the ground upwardly and then return the ripper to its desired position and effect further penetration.

The following patents are examplary of the prior art approach to this problem: US. Pat. Nos. 2,042,196; 2,817,168; 2,993,285; and, 3,038,267.

SUMMARY AND OBJECTS OF THE INVENTION In accordance with this invention an improved ripper in combination with a bulldozer having a blade with a lower ground-engaging edge, includes at least one socket forming a vertical edge at one end of a bulldozer blade and positioned so that the lower portion of the socket is forward of the upper portion of the socket with respect to the direction of travel of the bulldozer.

Mounted within the socket is a ripper adapted to be retracted into the socket or extended from it, with the degree of extension adjustable. Means are also provided to move the upper part of the ripper in a forward and backward reciprocating or oscillating motion along the direction of travel of the bulldozer and means are provided at the bottom of the socket to form a pivot point for the ripper.

It is the primary object of the present invention to provide a bulldozer blade with ripper means that is more effective than prior known devices.

Another object of the present invention is to provide a bulldozer blade with an oscillating ripper tip.

BRIEF DESCRIPTION OF THE DRAWINGS The invention can best be understood from the following specification when read with reference to the accompanying drawings, wherein:

FIG. 1 is a perspective view of a bulldozer blade having rippers in accordance with this invention at each end thereof and in extended position;

FIG. 2 is a sectional side view of a bulldozer blade having a ripper embodying this invention;

FIG. 3 is a schematic diagram of the mechanism employed in the embodiment of FIG. 2 to provide reciprocating motion to the ripper; and,

FIG. 4 is a sectional side view of an alternate modification of the ripper of this invention.

bulldozer. The blade 10 has a lower ground-engaging edge 12 and is provided on each side with a socket 13 containing a ripper 15. The ripper 15 is provided with a protective shin guard 16 and a removable tip 17 to O prevent excessive wear on the ripper shank itself.

The upper portion of the ripper is connected through a link 18 and a lever 20 with suitable pivots to the upper portion of the bulldozer blade 10. A hydraulic cylinder 21 is also pivoted to the center of lever 20 so that extension of the piston rod 22; moves lever 20 upwardly and causes ripper 15 to retract into socket 13 while retraction of piston rod 22 moves the lever 20 downwardly and causes ripper 15 to extend downwardly from socket 13.

As illustrated in FIGS. 2 and 4 "the socket 13 has a lower convergent portion 23 and an upper divergent portion 25. The lower portion 23 fits around ripper l5 snugly while the upper portion 25 provides adequate space for the upper portion of ripper 15 to move forward and backward with respect to the direction of the bulldozer in normal operation. The socket 13 also is tilted so that the lower portion 23 leads the upper portion 25 when the bulldozer is travelling in forward direction, and this tilt in the socket 13 provides for the ripper 15 to enter the ground at an angle with its tip 17 leading. A fulcrum for shank 15 is defined by a lower end wall 24 to support the shank for pivotal movement thereabout.

As illustrated in FIG. 2, a drive shaft 26 rotatably mounted in the upper portion of socket 13 and bearing against the upper portion of ripper 15 will, when rotated on its axis, cause eccentric pin 27 to produce reciprocal motion of the upper portion of ripper 15 within the socket 13. This motion will cause the tip 17 to move forward and backward in positions illustrated in solid and in broken lines in FIG. 2. Preferably, the tip 17 will extend about 12 inches below the ground level and will reciprocate about 2 inches between its forward-most and rearward-most positions.

FIG. 3 illustrates schematically a suitable mechanism for imparting reciprocating motion to the ripper 15. The eccentric pin 27 is shown bearing against ripper 15 and connected off-center to rotating shaft 26. Rotating shaft 26 is supported by suitable bearings 30 and is fixed to a gear which is a portion of a gear train 31. Other elements of gear train 31 are shown including portion 32 which is an internally geared element which includes a planetary gear train, not shown, for turning the shaft protruding therefrom. The mechanical means for imparting vibration to the ripper also includes a flywheel 33 and a suitable motor 35 which may be a hydraulic motor to impart rotary motion to the whole device.

When motor 35 is in operation, it builds up inertial energy in the flywheel 33 and at the same time rotates the gear train 31 so that the shaft 26 rotates on its axis. The offset pin 27 rotates so that for each revolution of the shaft 26 the upper portion of the ripper 15 is pushed back whereby the tip 17 is pushed forward. When the shaft 26 rotates the forward motion of the bulldozer will cause the upper portion of the ripper to move forward so that the upper portion of the ripper 15 is always in contact with the pin 27. In this way, the tip 17 of the ripper experiences an oscillating or slow vibrating motion with respect to the bulldozer which tends to break upwardly the crust of the ground being loosened by the action of the ripper.

FIG. 4 illustrates another suitable arrangement for providing reciprocating motion to the ripper 15. In FIG. 4, there is illustrated an arrangement wherein identical elements are identified by like numbers such as a bulldozer blade having a ripper attached to the end thereof. The ripper 15 is operated in a socket 13 that has a restricted bottom portion 23 and a diverging upper portion 25 to leave room for the upper portion of the ripper 15 to move back and forth as described with reference to FIG. 1. In the embodiment shown in FIG. 4 a link 36 is pivotally connected to the upper end of shank 15 and has an upper portion which is connected to a short-stroke hydraulic device or cylinder 37 which is capable of expanding and contracting over a short stroke and at a relatively high frequency such as 100 strokes per minute.

A bellcrank member 38 is pivotally connected at one end to the center of link 36 and at the other to the upper end of the blade 10. The extending and retracting jack 22 is pivotally connected to the center of bellcrank 38. An arm 39 of bellcrank 38 extends upward to which is connected one end of hydraulic cylinder 37.

When hydraulic device 37 expands and contracts, it is evident that the link 36 will move pivotally around a central pin 40 whereby the upper portion of the ripper 15 will move forward and backward in a relatively horizontal direction so that the tip 17 will move forward and backward with respect to the position of the bulldozer. The forward and backward motion of the tip 17 will be the same as that described with reference to FIG. 2 and will produce the upward breaking motion that is desirable to accomplish the purposes for which the ripper of this invention is designed.

As a result of the reciprocal motion at the top of the ripper and a pivot point at the bottom of the socket, the vibration or reciprocal motion of the tip of the ripper embedded in the ground causes an upward breaking effect that breaks hard ground and pries rocks and roots loose with an upward thrust so that ground that has been subjected to ripping becomes susceptible to being worked with a conventional bulldozer blade. It has been found that the vibration or reciprocal motion having an amplitude of about l-3 inches, preferably about 2 inches, is adequate to break most rocky or crusted ground, although for particular problems different amplitudes of vibration may be employed. It has also been found that the reciprocating motion maintained at a frequency of from about 50-150 cycles per minute, and preferably about 100 cycles per minute, breaks the ground upwardly for any velocity at which a bulldozer will normally be operated.

It is evident that within the scope of this invention many other means may be provided to produce the various functions that are required in the device claimed hereinafter. Many alternative devices may be provided to provide various functions, for example to extend or retract the ripper from the socket, to provide the reciprocating motion to the ripper, to provide pivot points about which the ripper may rotate.

What is claimed is:

1. In combination with a bulldozer having a blade with a lower ground-engaging edge, the improvement comprising:

a socket forming at least one end of said blade and positioned so that the lower portion of said socket is forward of the upper portion with respect to the direction of travel of the bulldozer,

a ripper shank mounted within said socket and movable between an extended position wherein it extends below said ground-engaging edge,

means in said socket intermediate the ends of said ripper shank to support said ripper shank and define a pivot point for said ripper,

means connected to the upper portion of said ripper shank to move said shank in a generally oscillatory motion about said pivot point in a direction corresponding to the forward and backward motion of the bulldozer, and

means to extend said ripper from and retract said ripper into said socket.

2. The combination of claim 1 wherein a socket and a ripper shank are mounted at both ends of the blade.

3. The combination of claim 1 wherein said means to move said ripper in an oscillatory motion comprise a rotating eccentric element in contact with the upper portion of said ripper.

4. The combination of claim 1 wherein said means to move said ripper in an oscillatory motion comprise a short-stroke hydraulic cylinder connected to move the upper portion of said ripper in an oscillatory motion with respect to said blade.

5. The combination of claim 1 wherein said means to move said ripper in an oscillatory motion are adapted to move the extended tip of said ripper through an amplitude of from about 1 to about 3 inches.

6. The combination in claim 1 wherein said means to move said ripper in an oscillatory motion are adapted to reciprocate said ripper at a frequency of from about 50 to about cycles per minute.

7. The combination of claim 1 wherein said socket closely embraces said ripper at the lower edge of said socket and diverges upwardly and includes means defining a pivot point at the bottom of the socket. 

1. In combination with a bulldozer having a blade with a lower ground-engaging edge, the improvement comprising: a socket forming at least one end of said blade and positioned so that the lower portion of said socket is forward of the upper portion with respect to the direction of travel of the bulldozer, a ripper shank mounted within said socket and movable between an extended position wherein it extends below said ground-engaging edge, means in said socket intermediate the ends of said ripper shank to support said ripper shank and define a pivot point for said ripper, means connected to the upper portion of said ripper shank to move said shank in a generally oscillatory motion about said pivot point in a direction corresponding to the forward and backward motion of the bulldozer, and means to extend said ripper from and retract said ripper into said socket.
 2. The combination of claim 1 wherein a socket and a ripper shank are mounted at both ends of the blade.
 3. The combination of claim 1 wherein said means to move said ripper in an oscillatory motion comprise a rotating eccentric element in contact with the upper portion of said ripper.
 4. The combination of claim 1 wherein said means to move said ripper in an oscillatory motion comprise a short-stroke hydrAulic cylinder connected to move the upper portion of said ripper in an oscillatory motion with respect to said blade.
 5. The combination of claim 1 wherein said means to move said ripper in an oscillatory motion are adapted to move the extended tip of said ripper through an amplitude of from about 1 to about 3 inches.
 6. The combination in claim 1 wherein said means to move said ripper in an oscillatory motion are adapted to reciprocate said ripper at a frequency of from about 50 to about 150 cycles per minute.
 7. The combination of claim 1 wherein said socket closely embraces said ripper at the lower edge of said socket and diverges upwardly and includes means defining a pivot point at the bottom of the socket. 